Peerguardian 2 virus??

I have PeerBlock on my computer which starts up automatically but today a window popped up after startup saying something along the lines of "Peerguardian 2 cannot run whilst PeerBlock is running. Please close and restart". I haven't even heard of Peerguardian 2 let alone chosen to download it so I was suspicious about whether it was a virus. Googling it though is giving a bit of a mixed opinion - it seems to be a genuine program but I also came up with lots of results about it being a particularly nasty trojan. I'm inclined to believe the latter in my case as I recently reformatted my computer so it normally runs fairly fast but is being particularly slow to respond today.
Anyone know whether it is a virus and how to safely remove it? I cant find it on my computer anywhere to uninstall (even in control panel programs or task manager).

Thanks